Items tagged with EFFICIENCY Files

File size: 1.17 MB Download

Ventilations filters: Field test of efficiency (NT VVS 128)

NT VVS 128

  • This Nordtest method is intended to be used in testing ventilation filters in their normal operating conditions. The purpose of the test is to determine if the fractional efficiency of the filter(s) differs significantly from that expected from the laboratory tests.

File size: 58.18 KB Download

Anti-scale devices: Efficiency (NT VVS 126)

NT VVS 126

  • The objective of the test method is to test the efficiency of anti-scale devices. The efficiency is determined by measuring the amount of scale on a heating element in a water heater equipped with treated water compared with the amount of scale on a blind installation without water treatment.

File size: 121.20 KB Download

Large solar collector arrays: In-situ efficiency test (NT VVS 097)

NT VVS 097

  • The purpose of the test method proposed in this report is to be able to check the efficiency of solar collector arrays, based on in-situ measurements with only a few measuring channels and relatively short measuring time.


Nordtest is a trademark of Nordic cooperation in conformity assessment. The emphasis of Nordtest is to develop, promote and innovate Nordic test methods and pre-normative activity. Nordtest endeavours to remove technical barriers to trade and promotes the concept: “Approved once, accepted everywhere”.